All patient-level HPO phenotypes from the WES study (>2,000, prefix “MWES”)

in addition to paediatric molecular confirmed patients from the mitoNET and Besta registries (>300, prefix “MREG”)

paediatric molecular confirmed Leigh syndrome patients from the Beijing Leigh Group Project (>200, prefix “BLGP”)

and paediatric molecular confirmed patients curated from the literature (>1,500, prefix “MLIT”)

Total number of patients

## [1] 7746

Patients with a molecular diagnosis

## [1] 6838